Reading data from external device thru MXJ ?

I have a system that takes in data from an external device (an EEG headset), and sends the signals into a Max patch to be converted into audio in realtime. In between the device and Max, there are Python and Java components. The data flows into the patch through [mxj] but for some reason, the rate at which the patch reads the incoming values is excessively slow, despite the Java script itself running smoothly.

I’m trying to get it to read sets of 8 24-bit values (so 8 values in each set) at whatever rate it can handle (the EEG data itself is generated at 500 Hz, but I only need it to read at about 50 Hz). But at anything faster than a mere 4 Hz, the read process starts acting sluggishly and missing values. I don’t think it’s because my patch requires too much processing power, since the situation is mostly the same even if I clear out everything except for the bare infrastructure.

Is mxj known to do this? Does anyone know how I could get it to handle a more rapid stream of data? Advice would be much appreciated.